1. FIELD OF THE INVENTION
The present invention relates to disposable absorbent articles and more particularly to female sanitary napkins. Particularly, the present invention concerns sanitary napkins having flaps and a stress relief means for relieving the stresses that develop in the flaps when the flaps are folded down and under a wearer's undergarment.
2. BACKGROUND ART
All manner and variety of absorbent articles configured for the absorption of body fluids such as menses, urine, and feces are, of course, well known. Particularly, sanitary napkins having flaps are disclosed in the literature and are available in the marketplace.
Generally, the flaps extend laterally from a central absorbent means and are intended to drape over the edges of the wearer's panties in the crotch region. Thus, the flaps are disposed between the edges of the wearer's panties in the crotch region and the wearer's thighs. Commonly, the flaps are provided with an attachment means for affixing the flaps to the underside of the wearer's panties.
The flaps serve at least two purposes. First, the flaps prevent exudates which otherwise would soil the edges of the wearer's panties from doing such. Second, the flaps help stabilize the napkin from shifting out of place, especially when the flaps are affixed to the underside of the panties.
Sanitary napkins having flaps of the general type described are disclosed in U.S. Pat. No. 4,687,478, entitled "Shaped Sanitary Napkin With Flaps", which patent issued to Van Tilburg on Aug. 18, 1987, U.S. Pat. No. 4,608,047, entitled "Sanitary Napkin Attachment Means", which patent issued to Mattingly on Aug. 26, 1986, U.S. Pat. No. 4,589,876, entitled "Sanitary Napkin", which patent issued to Van Tilburg on May 20, 1986, U.S. Pat. No. 4,285,343, entitled "Sanitary Napkin", which patent issued to McNair on Aug. 25, 1981, U.S. Pat. No. 3,397,697, entitled "Disposable Sanitary Shield For Undergarments", which patent issued to Rickard on Aug. 20, 1968, and U.S. Pat. No. 2,787,271, entitled "Sanitary Napkin", which patent issued to Clark on Apr. 2, 1957.
While sanitary napkins having flaps are commonly viewed as providing better protection soiling as compared to sanitary napkins without flaps, the flapped napkins commonly experience a problem that keeps them from being optimally effective. The problem is that the flaps sometimes become detached from the underside of the wearer's panties.
When the flaps are folded down along the edges of the wearer's panties, stresses are created in the flaps. The stresses are especially high along the fold line at the edges of the wearer's panties where the flaps are bent from the bodyside of the panty to the underside of the panty. These stresses are magnified when a wearer sits or crouches because the edges of the panties are pulled outwards against the flaps thus increasing the forces against this fold line. When the stresses become too high, the flaps may become detached from the panty and some portion of the aforementioned benefits of the flaps may be lost. Thus, there is a commercial need for a way of eliminating or at least reducing the stresses that develop in the flaps when folded, so as to prevent them from becoming detached from the wearer's panties.
Therefore, it is an object of the present invention to provide a sanitary napkin having flaps and a stress relief means for relieving the stresses that develop in the flaps when they are folded down along the edges of the wearer's panties in the crotch and affixed to the underside of the panties.
It is an additional object of the present invention to provide a sanitary napkin having flaps wherein a slit is provided in the flaps or along the line of juncture between the flaps and the central absorbent means of the napkinn so as to relieve the stresses that develop in the flaps when they are folded.
It is an additional object of the present invention to provide a sanitary napkin having flaps wherein a notch is provided in the flaps or along the line of juncture between the flaps and the central absorbent means of the napkin so as to relieve the stresses that develop in the flaps when they are folded.
It is an additional object of the present invention to provide a sanitary napkin having flaps wherein at least one stress relief means is provided at each longitudinal side of each flap.
These and other objects of the present invention will be more readily apparent when considered in reference to the following description and when taken in conjunction with the accompanying drawings.